Fatal crashes of passenger vehicles before and after adding antilock braking systems.

Fatal crash rates of passenger cars and vans were compared for the last model year before four-wheel antilock brakes were introduced and the first model year for which antilock brakes were standard equipment. Vehicles selected for analysis had no other significant design changes between the model years being compared, and the model years with and without antilocks were no more than two years apart. The overall fatal crash rates were similar for the two model years. However, the vehicles with antilocks were significantly more likely to be involved in crashes fatal to their own occupants, particularly single-vehicle crashes. Conversely, antilock vehicles were less likely to be involved in crashes fatal to occupants of other vehicles or nonoccupants (pedestrians, bicyclists). Overall, antilock brakes appear to have had little effect on fatal crash involvement. Further study is needed to better understand why fatality risk has increased for occupants of antilock vehicles.